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charset="UTF-8" X-Rspamd-Queue-Id: 87A354000A X-Stat-Signature: ptpiqoda8ra9kyg1r7hu3picgiy9wttb X-Rspam-User: X-Spamd-Result: default: False [3.10 / 9.00]; SORBS_IRL_BL(3.00)[209.85.219.42:from]; BAD_REP_POLICIES(0.10)[]; RCVD_NO_TLS_LAST(0.10)[]; MIME_GOOD(-0.10)[text/plain]; BAYES_HAM(-0.00)[38.93%]; RCVD_COUNT_TWO(0.00)[2]; MIME_TRACE(0.00)[0:+]; FROM_EQ_ENVFROM(0.00)[]; DMARC_POLICY_ALLOW(0.00)[google.com,reject]; RCPT_COUNT_TWELVE(0.00)[16]; DKIM_TRACE(0.00)[google.com:+]; TO_MATCH_ENVRCPT_SOME(0.00)[]; PREVIOUSLY_DELIVERED(0.00)[linux-mm@kvack.org]; R_DKIM_ALLOW(0.00)[google.com:s=20210112]; ARC_SIGNED(0.00)[hostedemail.com:s=arc-20220608:i=1]; FROM_HAS_DN(0.00)[]; R_SPF_ALLOW(0.00)[+ip4:209.85.128.0/17]; TO_DN_SOME(0.00)[]; ARC_NA(0.00)[] X-Rspamd-Server: rspam08 X-HE-Tag: 1670027929-564914 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: On Fri, Dec 2, 2022 at 4:35 PM Andrew Morton wrote: > > On Fri, 2 Dec 2022 16:26:05 -0800 Yosry Ahmed wrote: > > > Andrew, does this need to be picked up by stable branches? > > Does it? The changelog doesn't have a clear description of the > user-visible effects of the flaw, which is the guiding light for a > backport? > > There are 2 example scenarios in the changelog that misbehave without this fix, cases where the protection of a memcg that is the target of reclaim is not ignored as it should be. I would think that it needs to be backported to stable releases, unless Roman or any of the other memcg maintainers disagrees.